Travel chaos caused by an entirely unpronounceable Icelandic volcano has returned to Europe. A little more than a year after Eyjafjallajokull’s eruption grounded more than 100,000 flights across the continent, an ash cloud from the nearby Grimsvotn volcano closed various airports in northern Europe—although officials say that the disruption would not reach the scale of a year ago.

On Wednesday, Germany’s Bremen and Hamburg airports closed down because of ash in the air overhead, with traffic at Berlin’s airports due to stop later. Air traffic in Norway, Denmark and the UK was disrupted on Tuesday, but had returned to normal by Wednesday. Eurocontrol, Europe’s air traffic management agency, said about 500 of 29,000 flights scheduled across Europe had been cancelled on Tuesday.

Officials say that last year’s experience—which inconvenienced millions of passengers—resulted in amended flight rules in the case of volcanic ash that should prevent similarly large-scale air closures this year. What’s more, particles from Grimsvotn are larger than those emitted by Eyjafjallajokull, meaning that they will fall to the ground more rapidly. European Union transport commissioner Siim Kallas told the BBC: “We do not at this stage anticipate widespread airspace closure and prolonged disruption like we saw last year.”

But with Grimsvotn’s activity—and weather patterns around Iceland—impossible to predict, some airlines complained Wednesday that air traffic officials should relax restrictions even further. Michael O’Leary, the combative chief executive of budget airline Ryanair, announced on Tuesday that he had ordered one of his pilots to fly straight into the teeth of a giant volcanic ash cloud in an attempt to force regulators into lifting the ban by proving that air travel was safe. He called the ash cloud “‘non existent and mythical and misguided invention by the UK Met Office and the Civil Aviation Authority.’

UK officials, however, said that Ryanair’s aircraft—and the craft of another British Airways test flight which similarly encountered little particulant matter—had only gone through a zone already redesignated as safe. (via The Guardian)